Although they are designed primarily from the HSU platform, the "Outlaw" series of subs are primarily down-firing and have similar features though at somewhat less cost than the HSU's. I have the LFM-1 Plus in my system of multiple subs and it has excellent build quality and sounds great.

Have any of you guys seen or heard of these Linear Array Transducers(LAT) made by Tymphany? See the writeup as to how they work, it's quite interesting; they use several smaller diaphragms with two opposing end motors in a very small package, just a few inches and are claimed to be comparable to dual 8", 10", or dual 12" depending on the model. Kewell!! check'em out.

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